Development of climatic tests of polymer materials for extreme operating conditions

摘要

A review and analysis of changes in the mechanical properties of polymer composite materials (PCM) under natural climate tests based on foreign and domestic sources have been performed. Methodical features of measurements of mechanical parameters of PM and PCM are discussed to increase the reliability of estimates of their performance at the early stages of aging. To improve reliability of determination of mechanical properties of PCM during climatic aging in the initial state and after the completion of the next stages of exposure, methodological requirements are recommended. The following requirements should be met: sample preparation in accordance with current standards and preliminary assessments of monitored parameters; check of the variation of indicators and calculation of the coefficient of variation to ensure the required accuracy; study of the strength characteristics (compression, bending, stretching) for several temperatures, including below and above the glass transition temperature of the polymer matrix; measurements of controlled parameters of samples in the state of delivery or the moment of removal, after complete drying and moistening at 60°C. Compliance with the requirements will determine the number of samples required, the shape and size of the samples, methods of securing the samples in the clamps, the cutting angle of the samples to the main reinforcement direction.